1. Field of the Invention
The present invention relates generally to a loading mechanism for a data disk. Particularly, the invention relates to a disk loading mechanism which may be manufactured at low cost due to a simplified design and reduced number of parts.
2. Description of the Related Art
Floppy disks, optical disks, and other types of disk type data formats have become increasingly popular in homes and offices, being used for computers, word processors and other types of devices. Thus disk drives for reading and writing to such disks are a neccesary part of any environment utilizing such devices. One essential component of any disk drive is the disk loading mechanism, which allows the disk to be easily loaded into and ejected from the disk drive.
One such conventional disk loading mechanism is shown in FIGS. 5 and 6. Referring to the drawings, it may be seen that such a mechanism comprises a chassis 1 mounting a spindle motor 2 at a central lower side thereof. The spindle motor 2 is utilized to rotate a disk 3 for effecting disk reading and writing operations. The chassis 1 includes a central space for admitting the disk 3, which is usually loaded from an open front side of the disk drive (not shown). At a right side of a base plate la of the chassis 1, an L-shaped support wall 4 is formed with a opening 4a formed therethrough in the forward direction of the loading mechanism. The support wall 4 is positioned at a predetermined distance from a shaft 5 which is projected from the base plate 1a surface of the chassis 1. Also, at left and right forward areas of the chassis 1, first spring retaining projections 6, 6 are formed. Spaced along inner side walls 13, 13 of the chassis 1, vertically oriented inner grooves 7 are provided (in the drawing, only two grooves along the left side wall 13 are visible).
At left and right sides of both front and rear areas of the base plate 1a of the chassis 1, two pairs of disk positioning members 8, 8 and 9, 9 are disposed. The disk positioning members are mounted with a predetermined distance therebetween from right to left, and as seen in FIG. 6, the top sides of the rearmost disk positioning members 9, 9 are formed with circular cartridge position determining portions 9a, 9a thereon.
As best seen in FIG. 5, the conventional mechanism includes a slider plate 10 having an upturned C-shaped cross section. An eject button 11 is disposed on a tab 10a provided at a right front side of the slider plate 10. When the slider plate 10 is set into the chassis 1 as shown in FIG. 5, the spindle motor 2 is accommodated by a central U-shaped cut-out 12a, while a first pair of elongate grooves 12b, 12b admit the first spring retaining openings 6, 6. The slider plate 10 thus rests on the base plate 1a of the chassis 1 so as to be freely slidable thereon. The disk positioning members 8, 8, and 9, 9, engage second and third pairs of elongate grooves 14, 14 and 15, 15 for maintaining positioning between the chassis 1 and the slider plate 10 during sliding operation. In addition, projected from the base 12 of the slider plate 10 at a right rear side of the U-shaped cut-out 12a, a lock hook 17 is installed. Also, to the rear of each of the first elongate grooves 12b, 12b of the base 12 of tile slider plate 10, second spring retaining openings 16, 16 are formed. The second spring retaining openings 16, 16 respectively work in conjunction with the first spring retaining projections 6, 6 for mounting coil springs 20, 20 therebetween. The side walls 13, 13 of the slider plate 10 have four cam grooves 18 . . . 18 formed therein and, to the rear of the rearmost of the left side cam groove 18, a rack 19 is provided.
Referring to FIG. 6, a trigger arm 21 is pivotally mounted on the shaft 5 proximate the support wall 4 of the chassis. The trigger arm includes a side portion 21a and an end portion 21b as well as a projection 22 projecting upwardly from the surface of the trigger arm 21. The projection 22 is formed with a spring retaining opening 22a thereon. Pivotal movement of the trigger arm is determined by a torsion spring 5a disposed around the shaft 5. The ends of the torsion spring 5 are respectively attacted to the spring retaining opening 22a and the support wall 4.
Numeral 24 indicates a stepping motor for control of a head carriage 27. The stepping motor 24 is affixed to a rear side of the chassis 1 as seen in FIG. 5. An output shaft 25 of the stepping motor 24 is supported in the opening 4a of the support wall 4 and a V-shaped lead screw 25a is movable along the output shaft 25 according to a rotation thereof. A guide shaft 26 is provided extending in the front/rear direction of the mechanism, one end off the guide shaft 26 is attached to a rear side of the chassis 1 and guides movement of the head carriage 27 while the other end thereof is received in a support opening of a bush (not shown).
As may be seen, the head carriage 27 includes a needle pin 28 engaging the thread of the lead screw 25a of the output shaft 25, contact under pressure being maintained by a spring 29. Thus the head carriage 27 is supported so as to be freely moveable above the chassis 1.
At a forward side of the head carriage 27, a first disk read/write head 30 is supported. Opposed to the first disk read/write head 30, a second disk read/write head 31 is mounted. The heads 30, 31 are mounted on a head arm 32 supported by a flexible spring plate 33 so as to be swingably movable. Swinging movement of the head arm 32 is biased by a torsion spring 34. A stopper 32a projected from the side of the head arm 32 and integrally formed therewith is active to limit pivotal movement of the head arm 32.
Above the slider plate 10, a cartridge holder 36 is movably mounted. Rollers 37 of the cartridge holder 36 are rotatably supported between the cam grooves 18 of the slider plate 10 and the vertical grooves 7 of the chassis 1. Along one side of the cartridge holder 36, a cutout 38 is provided for forming a spring retaining projection 38a. The projection 22 of the trigger arm 21 is moved according to pressure from the insertion of the disk cartridge 3 into the loading mechanism such that the lock hook 17 contacts the side portion 21a of the trigger arm 21. Then, the slider plate 10 is brought adjacent to the base plate 1a dependent on forward motion of the slider plate 10. On the other hand, when the eject button 11 is pressed, the slider plate is urged to move rearwardly, causing the slider plate 10 to be separated from the base plate 1a.
A shutter opening/closing arm 39 is pivotally mounted on one side of the cartridge holder 36 for acting on a shutter 3a of the disk cartridge 3 for effecting opening or closing of the shutter 3a according to a loading or unloading operation of the disk loading mechanism respectively. The upper side of the shutter opening/closing arm 39 is integrally formed with a spring retaining projection 40. A coil spring 41 is held between the spring retaining projection 40 and the spring retaining projection 38a for biasing movement of the shutter opening/closing arm 39.
Further provided in such a conventional disk loading mechanism are a disk type (2DD, 2HD, 2ED) detecting switch 42 and a disk write protect mode detecting switch 43, which are connected to a printed circuit (not shown) provided on a circuit substrate 44 mounted at a lower portion of the chassis 1. Also, at a rear left portion of the chassis 1 a gear damper 45 is provided including a gear 46 engaged with the rack 19 of the slider plate 10 for smoothly controlling a loading and/of unloading operation.
Finally, the case 3b of the disk cartridge is provided with indentations 47 and 48 for engaging with the projecting disk positioning members 9, 9 mounted on the chassis 1 for suitably positioning the disk cartridge 3 for use.
According to the above structure, since two disk positioning members 8, 8 are required for height regulation of tile disk cartridge 3, and another two disk positioning members 9, 9 are utilized for horizontal positioning of the disk cartridge 3, and these members are formed separately from the chassis 1, a number of parts required for assembling a loading mechanism is increased and the cost and complexity of the mechanism is raised.
Thus, it has been required to provide a disk loading mechanism in which a number of parts and a cost of manufacture can be reduced.